1. Field of the Invention
The present invention relates to a liquid crystal display technology field, and more particularly to a transflective type blue phase liquid crystal display device and a liquid crystal display module of the same.
2. Description of Related Art
Comparing to the liquid crystal material used in the conventional liquid crystal display, the blue phase liquid crystal has four outstanding advantages: (1) a response time of the blue phase liquid crystal is within submillisecond, and no over-driving technology is required to achieve a high speed driving above 240 Hz so as to reduce a dynamic fuzzy of a moving image. When utilizing a RGB-LED as a backlight source, a color filter is not required, and using the blue phase liquid crystal can achieve a color timing display; (2) The blue phase liquid crystal does not require an alignment layer required by other types of display modes so as to simplify the manufacturing cost and reducing the cost; (3) Macroscopically, the blue phase liquid crystal is optically isotropic so that a blue phase liquid crystal display device has a wide viewing angle and good in a dark status; (4) When a thickness of a blue phase liquid crystal cell is greater than a penetration depth of an electric field, the influence transmittance by a change of the blue phase liquid crystal cell can be omitted. The above property is suitable for a large screen or a single panel liquid crystal display device.
However, in the conventional art, the blue phase liquid crystal faces a problem of too large driving voltage. Currently, an improved blue phase liquid crystal material is used or optimizing a structure of an electrode. However, the improved blue phase liquid crystal material is usually a blue phase liquid crystal material having a large Kerr constant. The above method relates to a complex process of synthesis of the blue phase liquid crystal material. For example, manufacturing a stable blue phase liquid crystal material requires considering a series of factors of monomer, photo initiator, and synthesis conditions. Accordingly, the development cost is very expensive. The method of optimizing a structure of an electrode utilizes an IPS (In-plane Switching) structure for driving, a penetration depth of a lateral electric field generated by parallel electrodes is limited, which requires a higher driving voltage. Therefore, the blue phase liquid crystal display technology using the IPS driving method still needs to be improved.
The reason that a display panel using the blue phase liquid crystal cannot adopt a vertical electric field is: when a voltage is applied on the display panel, under the function of a vertical electric field formed between a pixel electrode on an array substrate and a common electrode on a substrate oppositely to the array substrate, the blue phase liquid crystal is stretched in a vertical direction. When a polarized light passes through the blue phase liquid crystal stretched in the vertical direction, a phase of the polarized light does not change. A polarization state of the polarized light is the same as a voltage not applying on the blue phase liquid crystal. Besides, absorption axes of polarizing films of the liquid crystal display panel are perpendicular with each other. The light emitted from the backlight source cannot pass through the liquid crystal panel so that a bright status of the liquid crystal display panel cannot be obtained. Therefore, the above vertical electric field cannot be adopted to realize a display of grayscales of the blue phase liquid crystal display panel.
Because a liquid crystal display device is not an active light emitting device, and requires a backlight source to achieve a display effect so that a main display mode of the liquid crystal display device is a transmissive mode, which has a good readability indoors. However, under a strong sunlight or lighting, because of a reflective light of a surface of the liquid crystal display device, the readability in decreased. Generally, two methods are adopted to increase the readability outdoors: (1) increasing a brightness of the backlight source; (2) utilizing a reflective type liquid crystal display device. The first method obviously increases the power consumption. Therefore, the second method is usually adopted.